X-26 Frigate

__NOTOC__

The X-26 Program is the longest-lived of the X-plane programs. The program included the X-26A Frigate Sailplane and the motorized X-26B Quiet Thruster versions: QT-2, QT-2PC, and QT-2PCII. All were based on the Schweizer 2-32 Sailplane.

Development

The X-26A was used by the U.S. Navy (USN) to train test pilots in the condition of yaw/roll coupling. Since jet trainers were known to be dangerous in this condition, the X-26 was based on the Schweizer SGS 2-32 sailplane. Sailplanes react much slower and are easier to control than jet aircraft, making the X-26 a much safer training platform. Four aircraft were originally ordered. Three of the original planes crashed. The USN purchased a replacement for each of the crashed units.

Operational History

Two Schweizer 2-32s [(67-15345 and 67-15346) from the U.S. Naval Test Pilot School X-26 Program (USNTPS)] were modified to QT-2 configuration (QT for Quiet Thruster) by the Lockheed Missiles & Space Co. (LMSC) and designated N2471W and N2472W in 1967: Added a Continental Motors O-200 Engine, V-Belt RPM Reduction System, Four-Blade Fixed Pitch Wood (Fahlin) Propeller, and airframe up-grades. After demonstrating quiet flight, they were again modified to military QT-2PC configuration (known only as Tail Numbers "1" and "2"): Added GFE Avionics and camouflaged for night operation. They were successfully evaluated in Southeast Asia (Prize Crew OpEval) for covert (A.K.A. Stealth) tactical airborne observation in the Spring of 1968 (during TET). The two QT-2PCs were returned to USNTPS in 1969 and re-designated X-26Bs Notes:1. The #1 QT-2PC was re-designated "67-5345" and operated and the #2 Aircraft was used for spare parts.2. The original X-26 Glider version was then designated X-26A.

LMSC continued the covert airborne surveillance program with one Q-Star (House Test Aircraft) and eleven Pre-Preproduction YO-3As.

The X-26 Program is the longest-lived of the X-Plane Aircraft Programs.

The remaining X-26B Aircraft (known to most of the original development team (us) as QT-2 N2471W and QT-2PC #1) remains at the Army Aviation Museum (USAAM) at Ft. Rucker, ALThe other X-26B Aircraft (known to most of us as QT-2 N2472W and QT-2PC #2) has been retro-verted to SGS 2-32 Configuration and is being operated (and known as “72 Whiskey”) at Mile High Glider in Boulder, CO.

The Q-Star was the first aircraft to use a Rotary-Combustion-Chamber (Wankel) Engine. It is currently being returned to flight status.

The YO-3As were tactically evaluated in Southeast Asia from mid 1969 to late 1971. They were later used by the Louisiana Dept of Wildlife & Fisheries (LDWF) and the Federal Bureau of Investigations (FBI) in law enforcement and NASA for scientific applications. YO-3A 69-18007 is currently being returned to flight status. YO-3A 69-18010 (NASA 818) is down for an engine upgrade.

See quietaircraft.org, prizecrew.org, and YO-3A.com for additional information/art.

pecifications (X-26A Frigate)

aircraft specifications

plane or copter?=plane
jet or prop?=prop
crew=two
length main=26 ft 9 in
length alt=7.92 m
span main=57 ft 1.5 in
span alt=17.37 m
height main=9 ft 3 in
height alt=2.74 m
area main=180 ft²
area alt=16.7 m²)

Aspect ratio: 18:1
empty weight main=857 lb
empty weight alt=389 kg
loaded weight main=1430 lb
loaded weight alt=650 kg
max takeoff weight main= lb
max takeoff weight alt= kg
max speed main=158 mph
max speed alt=254 km/h)

Rate of sink: 0.6 m/s (120 ft/min)
range main= miles
range alt= km
ceiling main= ft
ceiling alt= m
climb rate main= ft/min
climb rate alt= m/s
loading main=39 kg/m²
loading alt=7.9 lb/ft²
power/mass main= 0.07 hp/lb
power/mass alt= 0.12 kW/kg

pecifications (X-26B and QT-2PC))

aircraft specifications

plane or copter?=plane
jet or prop?=prop
crew=two
length main=30 ft 9 in
length alt= m
span main=57 ft 1.5 in
span alt=17.37 m
height main=9 ft 3 in
height alt=2.74 m
area main=185 ft²
area alt=16.7 m²)

Aspect ratio: 18:1
empty weight main= lb
empty weight alt= kg
loaded weight main=2500 lb
loaded weight alt= kg
max takeoff weight main= lb
max takeoff weight alt= kg

engine (propulsion)= Continental O-200 horizontally opposed 4-cylinder air-cooled engine
power main= 100 hp
power alt= 75 kW
number of props= 1 (Ole Fahlin)four-blade, 8 inch Chord, fixed-pitch 100 inch Diameter
Fuel Capacity= 20 (nominal)Gal
Quiet Cruise speed main= 70-80 mph
Quiet Cruise alt= km/h)

Rate of sink: m/s ( ft/min)
Endurance, Planned = 4+ Hours, Demonstrated = 6.7+ Hours
ceiling main= 13,000 ft
ceiling alt= m
climb rate main= 200 ft/min
climb rate alt= m/s
loading main= kg/m²
loading alt= lb/ft²
power/mass main= hp/lb
power/mass alt= kW/kg

ee also

aircontent
related=
* Schweizer SGS 2-32
* Army-Lockheed YO-3A
similar aircraft=
* Scheibe SF25C
lists=
* List of experimental aircraft
see also=

References

* [http://history.nasa.gov/monograph31.pdf American X-Vehicles] (.pdf)

QT-2, QT-2PC, Q-Star, and YO-3A

QT-2, QT-2PC, Q-Star, and YO-3A